Apparatus foe obtaining metals of the alkalies feom molten



' (No Model) L. GRABAU. APPARATUS POR OBT-AINI'NG METALS 0F THE ALKALIES FROM .MOLTEN OHLORIDEL Patented Deo.

H all' L IIIIIHIIIIII "me mms Perini cuA. wom-mmf, WASHINGTON, n. c.

UNITED STATES PATENT OFFICE.

LUDIVIG GRABAU, OE HANOVER, GERMANY.

APPARATUS FOR OBTAlNlNG METALS OF THE ALKALIES FROM MOLTEN CHLORIDE.

' SPECIFICATION forming part of Letters Patent No. 464,096, elated December 1, 1891.

Application tiled November 15, 1889. Serial No. 330,458. (No model.) Patented in Germany October 8, 1889, No. 51,898; in Belgium October 8,1889, No. 88,001; in FranceOctober 8. 1889l No. 201,187; in England October 8,1889,No. 15.792; iu Italy October 8, 1889, XXIII, 26,300, LIII, 44; in Switzerland October 8, 1889, No. 1,471 in Spain November 25, 1889, No. 10,018, and in Austria-Hungary March 8. 1890, No. 43,733 and No. 4,471.

To all whom it may concern:

Be it known that I, LUDWIG GRABAU, engineer, a subject of the German Emperor, residing at Hanover, Prussia, German Empire, have invented certain new and useful Improvements in Apparatus for Obtaining Metals of the Alkalies from Molten Chloride, `(for which I have obtained Letters Patent in the following countries: in Germany, dated Octoloer 8, 1889, No. 51,898; in Belgium, dated October 8, 1889, No. 88,001; in France, dated October 8, 1889, No. 201,187; in England, dated October 8, 1889, No. 15,792; in Italy, dated October 8, 1889, Vol. 23, No. 26,300, and Vol.53, No. 44; in Austria-Hungary, dated March 8, 1890, No. 43,733 andy No. 4,471; in Spain, dated November 25, 1889, No. 10,018, and in Switzerland, dated October 8, 1.889, No. 1,471

and I do hereby7 declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and usev This invention is an improvement on ap-.

paratus described in Letters Patent granted t to me in England under date of July 14, 1887,

No. 9,904, and on apparatus'described in an application for Letters Patentof the United States of America filed by me on or about the 9th day of August, 1887, Serial N o. 246,528.

All attempts to obtain the metals of the alkalies on a large scale from the molten or liquid chlorides by means of electrolysis heretofore made, and with which we are acquainted, have not proved successful, inasmuch as it has been found impossible to keep up a regular course of operation for a sufficient length'of time owing to the rapid destruction of the apparatus, this destruction taking place in the cell of the pole designed for the reception of the metal deposited. As these cells must be made of a fire-proof material, which ever, established that the speedydestructionl ofthe pole-cells is not due to the direct destructive action of 'the metal of the alkalies, but that the real cause of this action seems to be due to the fact that the electric current passes through the Walls of the cell. In fact,

it has been found that even well-glazed porcelain cells-are capable of conducting electric currents` so that their walls were soon broken through. y

The object of this inventionl is to obviate this detrimental action of the electric currents by means of a pole-cell of' such oonstruction as to prevent the passage of the electric current through its Walls. This result is attained, aceordingto the present invention,by means of an annular partition-wall extending from the lower edge of the bellshaped pole cell to a point above the surface of the molten mass, so that conductivity between the material within the pole-cell and the material surrounding the same can only take place through the open lower end of the cell, but not through the walls thereof.

In the accompanying drawing I have shown in vertical axial section an apparatus constructed according to my present invention.

The apparatus consists of a melting pot or vessel A, inclosed within a larger vessel to form an encompassing air-jacket L. The vessels A L are preferably heated by hot gases, which pass through ducts G.

I do not wish to limit myself to the arrangement of the tWo vessels A L to form a space between them, as any other construction of t able refractory material, and also the carbon electrodes C, these being arranged around the pole-cell B. The pole-cell B is inclosed within a chamber formed by an annular partition w, that extends from the lower edge of the cell up through and projects beyond the surface N N of the molten mass. A space is thus left between the wall 1o of the cell and the partition w, from which the molten mass is excluded. The said molten mass, therefore, does not come in contact with the outer surface of the cell-walls p, and an electrical connection between themolten mass inside and outside the pole-cell through the walls thereof is therefore impossible.

E is a tubular support for the pole-cell B, said support having its lower end screwthreaded, and is provided with a dischargepipe a, that discharges into a receiver or collector S. The pipe a, as shown, is secured in an enlargement of the support E, which enlargement provides an annular shoulder or seat e for the upper end of the inner contracted portion or neck b of the pole-cell B, a suitable packing b being interposed between said neck and shoulder or seat. The cell B ,is firmly secured to the support Eby means of a nut n screwed onto the lower end of said support, a packing b2 being interposed between said nut and the neck b of cell B, as

shown. Any other means may, however, be resorted to for securing the cell to its support.

The support E is preferably made of iron and constitutes the negative electrode, and its conducting-surface is preferably increased by attaching thereto a wire n2, that extends nearly to the lower open end of the cell, and by attaching to said wire a metallic crosspiece fn, for the purpose of reducing the resistance of the molten metal to the passage of the electric current.

A boring-tool H is connected with and eX- tends into the tubular support E for the purpose of removing obstructions.

The specic gravity of the metals of the 'alkalies being less than that of the molten chlorides, the liquid metal collected in the pole-cell rises to the surface of the molten mass, and as it forms in the cell it flows through the discharge-pipe Ct and is collected outside of the decomposing apparatus in the receiver M. The receiver employed for collecting the metal may consist of a vessel S, filled with petroleum, into which dips a bellshaped or cylindrical vessel M, open at its lower end and connected at or near its upper end with the discharge-pipe a, the said vessel M being preferably kept filled with any suitable gas-such as hydrogen or nitrogenthrough the medium of a pipe c, connected with the top of said vessel. The chlorine developed is drawn off throughl a pipe d, connected with the melting-vessel A, while the salt supply isintroduced through a feedaperture e in the top of the said chamber.

Having described` my invention, what I claim, and desire to secure by Letters Patent,

l. In an electrolytical apparatus, the combination, with the containing-vessel or melting-pot and one of the electrodes, of a polecell for said electrode, constructed with double walls inclosing a chamber that'is open atthe 75 top, for the purpose set forth.

2. VIn an electrolytical apparatus, the combination, with the melting-pot and one of the electrodes and a tubular support for said electrode, having a discharge-pipe connected 8o therewith, of a bell-shaped polecell constructed of refractory material and with double walls inclosing a chamber that is open at top, said cell being connected with the support .below the discharge-pipe, substan- 85 tially as and for the purpose specified.- l

3.. In an electrolytical apparatus, the combination, with the melting-pot and one of the electrodes, of a tubular support for said electrode, a discharge-pipe connected with said 9o support, and a cell suspended therefrom and constructed with double walls inclosing a chamber that is open at top, for the purpose set forth.

In testimony whereof I affix my signature in 95 presence of two witnesses.

" LUDWIG GRABAU.A

Witnesses:

MAX EPSTEIN, W. KEssLER. 

